In a groundbreaking study conducted by researchers at the Indian Institute of Technology Madras (IIT-M) and Karkinos Healthcare, it has been revealed that nearly one in four breast cancer patients in India possess inherited genetic variants linked to cancer. This significant finding, published in the peer-reviewed journal BMC Cancer, highlights the necessity for a shift away from traditional BRCA-only testing and advocates for broader genetic screening methods tailored to the Indian demographic.
Study Overview and Key Findings
The study analyzed germline DNA from 479 unselected breast cancer patients, utilizing samples from the National Cancer Tissue Biobank at IIT-M. This research is now part of the Bharat Cancer Genome Atlas, which stands as India's largest open-source cancer genome data resource. By examining 97 cancer susceptibility genes, including the well-known BRCA1 and BRCA2, the research team identified a significant prevalence of mutations occurring outside these commonly tested genes. Learn more on World Health Organization.
According to the study, 24.6 percent of the patients analyzed carried at least one pathogenic or likely pathogenic variant. While 8.35 percent had mutations in either BRCA1 or BRCA2, an alarming 11.9 percent were found to have inherited mutations in other homologous recombination repair genes. Notably, 67 percent of all positive findings were associated with non-BRCA genes such as MLH1, NF1, TP53, and RB1. These statistics point to a pressing need for more comprehensive testing in the Indian population.
The Urgency for Broader Testing
Lead author S Mahalingam, head of the National Cancer Tissue Biobank at IIT-M, emphasized the implications of these findings for clinical practice and public health policy. He stated, "With around one in four Indian breast cancer patients carrying an inherited pathogenic variant, and most of these variants lying outside BRCA1/2, the study makes a compelling case for shifting from BRCA-only testing to broader multi-gene panel or exome-based germline testing in India."
Mahalingam further noted the critical need for the establishment of India- and South Asia-specific variant databases, which would greatly enhance the accuracy of risk assessments for patients. This shift could lead to better-targeted prevention and treatment strategies for breast cancer in the region.
Uncovering Additional Health Risks
Beyond the focus on cancer predisposition, the study also uncovered clinically significant secondary findings. More than 21 percent of the patients were found to carry actionable variants in non-cancer genes associated with various health conditions such as Marfan syndrome, malignant hyperthermia susceptibility, inherited cardiac arrhythmias, and familial hypercholesterolemia. Additionally, around 8 percent were carriers of recessive disorders, including biotinidase deficiency and Wilson disease.
This broad spectrum of findings indicates that comprehensive germline sequencing can reveal health risks that extend beyond cancer, thereby enabling better-informed healthcare decisions. Dr. John Peter, the first author of the study, commented, "A comprehensive germline sequencing can uncover health risks beyond cancer predisposition, enabling healthcare providers to offer a more holistic approach to patient care."
Implications for Future Cancer Research
The research conducted by IIT-M and Karkinos Healthcare not only sheds light on the genetic landscape of breast cancer in India but also sets a precedent for future cancer research in the country. By demonstrating the prevalence of inherited genetic variants outside of the BRCA genes, this study paves the way for more inclusive testing methods that can better capture the genetic diversity of the Indian population.
As the healthcare landscape continues to evolve, the integration of advanced genetic screening into routine clinical practice will be crucial. The findings highlight the urgent need for healthcare policies that support the development of multi-gene testing approaches and the establishment of comprehensive genetic databases tailored to the unique genetic makeup of the Indian population.
So, this landmark study emphasizes the importance of expanding genetic testing protocols in India. As researchers and healthcare professionals work towards implementing these changes, the hope is that early detection and personalized treatment options can significantly improve outcomes for breast cancer patients across the nation.
Originally reported by Dt Next. View original.